Originally posted by mee Why? You went 1 stop on aperture (adjusting for DoF?) and 1 stop up on ISO ( ???). So 2 stops difference.
For equivalent AOV, DOF and exposure, the focal length and f/stop scale with the crop factor and the ISO with the crop factor squared (since the total light is the same, but the sensor area is 1.5^2 larger for FF, so the light intensity drops by the same amount). So yes, ISO scales
up for FF, not down, so if you move to FF, you better get used to using higher ISO settings. Mind you, higher ISO does not imply more noise when changing the format. See for instance
here for more details.
Originally posted by mee Even if the karts were standstill and the photog using a tripod.. at ISO 12000 it would look awful due to the camera's high ISO performance. And the cleanup work is going to be tough to impossible because the data available to use is limited (vs having used a much lower ISO value). DR is squashed to smithereens at that ISO level.
It does suffer for sure, but what are the options with the given parameters? You can't open the aperture any wider than 2.8 with this lens, and you can't possibly drop the shutter speed without making things worse. In fact, I wouldn't be surprised if the shot were better with double the ISO for the sake of a faster shutter speed.